Instrument mounting assembly with timer camming arrangement

ABSTRACT

An instrument or timer mounting assembly which comprises an instrument or timer module and its mating mounting receptacle adapted to receive therein the instrument or timer module. This mounting assembly is provided with a manually operable handle formed near its open ends with a pair of fingers; one of which is adapted to draw the module toward the mating receptacle as the handle is rotated to secure the module to the receptacle and the other of which is adapted to separate the module, that has been secured to the receptacle, away from the receptacle, based on the principle of leverage, as the handle is rotated in the opposite direction.

United States Patent [191 Muranaka [451 July 17, 1973 1 INSTRUMENT MOUNTING ASSEMBLY WITH TIMER CAMMING ARRANGEMENT [75] lnventor: Tsutomu Muranaka, Okayama,

2: Appl. No.: 276,308

[30] Foreign Application Priority Data July 31, 1971 Japan 46/68712 [52] US. Cl. 317/99, ZOO/38 R, 248/27, 339/45 R [51] Int. Cl H02!) [58] Field 01 Search 248/27; 339/45 R,

339/45 M; 174/91 R; 200/56 R, 168 A, 168 B, 168 C, 38 R, 39 R, 39 A, 169 R; 317/99, 101 -R, l0lCB, 118,120

[5 6 Referencesv Cited UNITED STATES PATENTS 3,054,023 9/1962 Blecker 317/113 Primary Examiner-Robert K. Schaefer Assistant Examiner-Gerald P. Tolin Attorney-Paul M. Craig, Jr., Donald D. Evenson et a1.

[5 7] ABSTRACT An instrument or timer mounting assembly which comprises an instrument or timer module and its mating mounting receptacle adapted to receive therein the instrument or timer module. This mounting assembly is provided with a manually operable handle formed near its open ends with a pair of fingers; one of which is adapted to draw the module toward the mating receptacle as the handle is rotated to secure the module to the receptacle and the other of which is adapted to separate the module, that has been secured to the receptacle, away from the receptacle, based on the principle of leverage, as the handle is rotated in the opposite direction.

22 Claims, 7 Drawing Figures Patented July 17, 19.73

2 Sheets-Sheet 1 Patented July 17, 1973 I 3,746,931

2 Sheets-Sheet 2 FIG. 3

The present invention relates to an instrument or timer mounting assembly comprising an instrument or timer module and a mounting receptacle into or from which the module is engaged or disengaged, respectively, without connecting or disconnecting the wires connected to the electrical circuits controlled by the instrument or timer housed in the module.

More particularly, the present invention pertains to a timer or counter mounting assembly which comprises an operating handle, a timer or counter module having a plurality of electrical plugs on the rear of the counter or timer and a mounting receptacle adapted to be permanently installed on the control panel or the like, wherein the module is adapted to be slipped into the mounting receptacle with the electrical plugs forced to firmly engage with a plurality of electrical sockets on the rear of the mounting receptacle as the handle is rotated in one direction and, as the handle is rotated in the opposite direction, the module can be disengaged from the receptacle with the electrical plugs disconnected from the electrical sockets.

This type of instrument or timer mounting assembly is, according to those skilled in the art, referred to as a plug-in electro-mechanical device and known as having such various advantages that, in view of the fact that the module can be easily and readily engaged into or disengaged from the mounting receptacle, not only sapre timers or counters may be kept on hand for emergency use and the replaced timer repaired at leisure, but also the module housing therein a timer or counter of different type can be utilized in association with the receptacle of the same type, and that maintenance of the device itself is easy and does not incur any substantial cost thereof.

In view of these advantages, various types of plug-in posed. However, in order to insure the reliability of performance of the plug-in electro-mechanical device, firm engagement between the electrical plugs and the electrical sockets must be essential. Preferably, this firm engagement therebetween must be obtained by the application of a slight pushing force to the handle whose rotation in one direction causes the instrument or timer module to be drawn into the mounting receptacle. On the other hand, this firm engagement must be released as the handle is rotated in the opposite direction with the application of a slight pushing force thereto.

The US. Pat. No. 3,054,023 patented on Sept. ll, I962 discloses an exemplary type of plug-in electromechanical device of similar character wherein the above mentioned factors determinant of the reliability of performance of the device have been taken into consideration. According to this US; Patent, the plug-in electro-mechanical device includes a handle pivotally supported by a pin on both sides ofa timer module and having a pair of free open ends each formed with an arcuate shaped finger having an inwardly arched edge engageable with a pin provided on both sides of the open end of a mounting receptacle. In this arrangement, as

the handle is rotated aboutthe pin on both sides of the timer module, the latter is drawn into the mounting receptacle with the inwardly arched edge of the finger in sliding engagement with the pin on both sides of the open end of the mounting receptacle and, as the timer module is drawn into the mounting receptacle in the abovementioned manner, the electrical plugs on the rear of the timer module can be engaged into the corresponding electrical sockets on the rear of the mounting receptacle.

Rotation of the handle in the opposite direction causes the timer module to be disengaged from the mounting receptacle with the electrical plugs disconnected from the electrical sockets.

According to the plug-in electro-mechanical device of the above numbered patent, the principle of leverage is employed in such a way that the pin on the both sides on the front of the the timer module provides a fulcrum about which the handle pivots whereby a slight force applied to the handle can be converted into a great force at the free open ends of the handle which is utilized to selectively engage and disengage the timer module into and from the mounting receptacle depending upon the direction of rotation of the handle.

However, there can be still found disadvantages in the plug-in electro-mechanical device of the above numbered patent. In view of the fact that the fulcrum of leverage is provided on the side of the timer module which is movable relative to the mounting receptacle, the position of the pin supporting the handle which serves as the fulcrum for pivotal movement of the handle displaces from the alignment between the module and the receptacle accompanying a corresponding displacement of the module. Therefore, the operation of the device cannot rely on the handle for mounting the timer module on to the mounting receptacle, or otherwise he must use his both hands in such a way that one of the hands is used to support the timer module while the other hand is used to operate the handle.

In addition thereto, the timer module has a tendency to fall by gravity with respect to the mounting receptacle at the time the finger on both free open ends of the handle commences to engage with the pin on both sides of the front end of the mounting receptacle. In view of this, it is apparent that, when the module is tightly engaged in the receptacle, the module assumes an inclined attitude with the rear of the module in register with the front of the receptacle and, hence, as the module is drawn into the receptacle while assuming the inclined attitude, a relatively greater friction takes place between the electrical plugs and the electrical sockets, or otherwise a reliable engagement therebetween cannot be obtained. The greater the friction is exerted therebetween, the lower the reliability is obtained in electrical connection achieved between the plugs and the sockets.

Furthermore, according to the above numbered patent, disengagement of the timer module from the mounting receptacle is carried out in such a manner that, as the handle is rotated in the opposite direction, the free end extremity of the finger is compelled to slidingly contact a portion of the front of the receptacle behind the pin to escape from the space between said pin and the front of the receptacle, thereby permitting the module to be automatically moved a distance away from the receptacle.

Since the principle of leverage is employed, the slighter pressure applied on a portion of the handle touched by the hand so as to move the handle to a unlocked position results in the greater pressure on the free end extremity of the finger of the handle and,

hence, this greater pressure is transmitted to the portion of the front of the receptacle as said free end extremity of the finger contacts that portion of the receptacle front. Accordingly, it is clear that that portion of the receptacle front is susceptible to wear in the surface area corresponding to the path of travel of the free end extremity of the finger of the handle. This means that, in an extreme case, removal or separation of the module away from the receptacle cannot be carried out without any difficulty since the plugs are usually firmly inserted in the sockets while the handle and hence the finger no longer engage with that portion of the receptacle front.

Accordingly, an essential object of the present invention is to provide an improved instrument mounting assembly which can be installed and removed rapidly and easily with the substantial elimination of the above mentioned disadvantages inherent in the prior art mounting assembly of a similar character.

Another object of the present invention is to provide an improved instrument mounting assembly which generally comprises an instrument module, a handle pivotally supported by the instrument module and a mounting receptacle, said handle being adapted to implement a reliable engagement between the instrument module and the mounting receptacle.

A further object of the present invention is to provide an improved instrument mounting assembly of the type above referred to wherein the handle can be manually rotated to produce an effective force for smoothly drawing the instrument module on to the mounting receptacle to facilitate a reliable engagement between the module and the receptacle.

A still further object of the present invention is to provide an improved instrument mounting assembly of the type above referred to wherein the instrument module and the mounting receptacle are respectively provided with a plurality of electrical plugs and at least the corresponding number of electrical sockets, both of which are electrically engaged with or disengaged from each other in a horizontally aligned manner as the handle is rotated either of the opposite directions.

A still further object of the present invention is to provide an improved instrument mounting assembly of the type above referred to wherein the horizontally aligned engagement between the electrical plug and the electrical sockets ensures a reliable electrical connection between an operating mechanism housed in the module and the electrical circuits controlled thereby.

A still further object of the present invention is to provide an improved instrument mounting assembly of the type above referred to wherein no contact takes place between a portion of the receptacle front and the handle whereby no wearing of that portion of the receptacle front occurs.

A still further object of the present invention is to provide an improved instrument mounting assembly of the type above referred to wherein the handle is provided on both of its open ends with a pair of curved fingers, one of which is at its free end extremity formed with an inwardly extending recess about which said handle pivots when the handle is rotated so as to secure the module to the mounting receptacle and, when the module is to be removed or separated away from the receptacle, the handle pivots about a different fulcrum through which the handle is fitted to the module.

A still further object of the present invention is to provide an improved instrument mounting assembly of the type above referred to wherein the handle may be detachably fitted to the instrument capsule and hence the manufacture thereof can be simplified without requiring a complicated fitting procedure.

A still further object of the present invention is to provide an improved instrument mounting assembly of the type above referred to wherein the operator of the mounting assembly need not to utilize his both hands in mounting the module into the receptacle to achieve the above mentioned various objects.

According to the present invention, an essential feature thereof resides in the particular shape of the handle which is formed on both of its open or free ends with a pair of curved fingers defining a curved slot therebetween and loosely pivotally fitted to the instrument module. A first one of these fingers is adapted to engage in a sliding manner with a projection formed on both of the side surfaces of the front of the module to enable the latter to be drawn toward the mounting receptacle as the handle is rotated from the unlocked position to the locked position whereas the second finger has its free end extremity formed with an inwardly extending recess into which a pin secured on both of the opposed flanges of the front of the mounting receptacle is rotatably accommodated thereby permitting the handle to pivot so as to separate the module away from the receptacle when the handle is rotated in the opposite direction. Of course, the instrument module can be drawn straight into the mounting receptacle with the plug pins on the rear of the module firmly engaged in the sockets on the rear of the mounting receptacle. Separation there-between can be easily and readily carried out with the application of a reasonable force to the handle.

In the present invention, although the handle is pivotally supported by the instrument module, the fulcrum of leverage of the handle is served by a pin secured on both of the. opposed flanges of the front of the mounting receptacle, which rotatably engages in the inwardly extending recess in the second finger. This feature brings about an advantage that, at the time the instrument module is to be firmly engaged in the mounting receptacle, the front of the instrument module which is relatively heavier than the rear thereof will not tend to downwardly incline with respect to the mounting receptacle.

These and other objects and features of the present invention will become apparent from the following de scription to be made with reference to the accompanying drawings, in which;

FIG. 1 is a schematic perspective view of an instrument mounting assembly of the present invention,

FIG. 2 is an exploded view of the mounting assembly shown in FIG. 1,

FIG. 3 is a front view of the mounting assembly shown in FIG. 2, showing an outer appearance of the front of an instrument module secured to the mounting receptacle,

FIG. 4 is a perspective view, on an enlarged scale, of a handle used in the mounting assembly of FIG. 1,

FIG. 5 is a longitudinal side view of the mounting assembly of the present invention, showing the handle in the substantially horizontal or released position, with the enlarged fragmental portion of FIG. 5 showing the condition of an essential portion thereof,

FIG. 6 is a similar view to FIG. 5, showing the handle in the vertical or engaged position, and

FIG. 7 is a similar view to FIG. 5, showing the handle, that has been rotated to the engaged position, being in process of being rotated to the released position.

It is to be noted that the present invention can be applied in various way. For example, an instrument to be housed in the instrument module may be a timer, counter or emergency signalling device. Of course, any device other than the above listed may be used. In other words, the instrument mounting assembly of the present invention herein disclosed should be construed as utilizable in any field of application where such mounting assembly is necessitated.

Before the description of the present invention proceeds, it is to be noted that like parts are designated by like reference numerals throughout the several views of the accompanying drawings. In addition, it is to be noted that, for the sake of brevity, the description of the present invention will be made in connection with an electric timer mechanism operatively accommodated within a module of the construction herein disclosed.

Referring now to FIGS. 1 and 2, a mounting receptacle, generally indicated by is fixedly mounted to a suitable panel 20 such as control panel or wall of a housing structure in a manner as described below. The mounting receptacle 10 in the embodiment shown is of the type having a cylindrical body 9, one end of which is closed by a bottom or socket member (not shown) and the other end of which is open for accommodating therethrough a timer module and preferably integrally formed with a shaped flange 8, the plane of said shaped flange 8 being radially outwardly extending from the open end of said cylindrical body 9 of the mounting receptacle l0.

Loosely mounted on the mounting receptacle 10 is a supporting plate 11 having an area shaped to fit with the shape of the flange 8, a pair of frontwardly extending flanges 12 and 13 each formed with a pin 14 or 15 inwardly extending in register with each other, and a bore of a diameter substantially equal to the outer diameter of the cylindrical body 9 through which the latter extends.

The mounting receptacle 10 of the above construction is attached to the suitable panel with the cylindrical body 9 inserted through a bore formed in the panel 20 while the supporting plate 11 is interposed between the flange 8 of the mounting receptacle 10 and the panel 20 with the pair of the flanges l2 and 13 frontwardly projecting from the panel 20. For preventing the separation of these components 10, 11 and 20, a plurality of flat-headed screws (not shown) may be employed as tapped into the panel 20 through the flange 8 and then through the supporting plate 11.

It is to be noted that, without utilizing the supporting plate 11, the flange 8 of the of the mounting receptacle 10 may be provided on a pair of opposed edges with a pair of flanged portions substantially the same to the flanges l2 and 13 of the supporting plate 11.

The bottom or socket member (not visible) used to close the rear end of the cylindrical body 9 of the mounting receptacle 10 is, as is well known to those skilled in the art, provided with a plurality of terminal sockets (not shown) of the pass-through type which forms a part of the mounting receptacle 10. For this purpose, the bottom member is preferably made of electrically insulating material and, on the inside of the receptacle 10 the terminal sockets form sockets for terminal pins as will be mentioned later while, on the out-. side of the receptacle 10, they form screw terminals for external electrical connection. This bottom member may be, either integrally or separately, formed with the rear end of the cylindrical body 9.

The mounting receptacle 10 of the above construction so far described may be of the substantially same as disclosed in the US. Pat. No. 3,054,023 patented on Sept. ll, 1962.

The timer module is indicated generally by 30 and shown as including a cylindrical housing 31 having a rear end secured or integrally formed with an insulating ring 32. provided with the terminal pins 33 detachably engageable with the terminal sockets of the mounting receptacle 10 as hereinbefore described and the other front end provided with a bezel 34 of the shape preferably the same as that of the flange 8 of the mounting receptacle 10. The timer mechanism (not shown) is operatively accommodated within the cylindrical housing 31 and various operating components of the timer mechanism may be mounted onto the rear surface of the bezel 34 in any known manner. Some or all of the terminal pins 33 provided in the insulating ring 32 forming a part of the timer module 30 are utilized to connect electrical components of the timer mechanism within the cylindrical housing 31 to an external electrical credit (not shown) through the engagement between said terminal pins 33 and the corresponding terminal sockets formed in the bottom member of the mounting receptacle 10.

As shown, the bezel 34 has a pair of opposed top and bottom rims 34a and 34b and a pair of opposed side rims 34c and 34d, all surrounding a timer dial structure of the arrangement as will be described hereinafter with reference to FIG. 3.

The timer dial structure shown in FIG. 3 includes a calibration plate 35 having calibrated increments 35a the number of which varys with the timing range of the timer mechanism employed. This dial structure further includes a control knob 36 and a pair of pointer needles 37 and 38, the control knob 36 being adapted to permit the pointer needle 37 to set to a preset positionrepresenting the desired delay interval, accompanying the other pointer needle 38 to the same preset position. An arbitrary rotation of the needle 37 can be prevented by the provision of a suitable friction device (not shown), the provision of which is well known to those skilled in the art. The pointer needle 38 acts as a cycle progress indicator and is rotated at a controlled rate by the timer mechanism to show the time remaining with respect to the desired delay interval.

The calibration plate 35 may be designed such as to expose to the outside a pair of neon glow bulbs 39 and 40, either of which is utilized to indicate, for example, whether or not an electrical power from an external power source (not shown) is supplied to the timer mechanism while the other bulb is utilized to lighten, for example, at the lapse of the desired delay interval.

Referring back to FIG. I and with additional reference to FIG. 4, the bezel 34 is provided with a pivotable handle 50. The handle 50 is of the structure as clearly shown in FIG. 4 on an enlarged scale and has a grip-like portion 51 and a pair of arms 52 and 53, all arranged in channel or substantially U shape. The pair of the arms 52 and 53 are of the same size and configuration and, because of this, only one, i.e., 52, of said handle arms will be referred to in the following description for the sake of brevity. It is to be noted that like elements in either one of these handle arms are designated by like reference numerals in the other.

The handle arm 52 is formed on its free end with a pair of fingers 100 and 200 which define a curved slot 300 by means of curved edges 101 and 201 of said fingers 100 and 200, respectively, said curved edges 101 and 201 being opposed with respect to each other. One of the fingers such as indicated by 200 is formed with a substantially semi-circular recess at 202 engageable with one of the pins 14 or 15 formed in the supporting plate flanges 12 or 13 and also with a pin 203 projecting therefrom in parallel relation to the lengthwise direction of the griplike portion 51 of the handle 50, said pin 203 being located adjacent to the depth of said semi-circular recess 202.

While in the construction as hereinbefore described and shown in FIG. 4, the handle 50 is pivotally connected to the bezel 34 in such a manner that the pins 203 in the arms 52 and 53 is loosely accommodated in respective U-shaped notches which are formed in the opposed side rims 34c and 34d, respectively, and only one of which is shown by 34e in FIG. 2 or FIGS. 5 to 7. Each of the notches 34e has a sufficient surface area so that the corresponding one of the pins 203 in the fingers 200 can move from one point to another within said surface area of the notch. It is to be noted that the depth of each one of said notches 34e is preferably slightly smaller than the height of the corresponding one of the pins 203.

The side rims 34c and 34d are each provided with projections of substantially circular cross section, only one of which is shown by 34f in FIG. 2 or FIGS. 5 to 7, said projections 34f being arranged such as to locate within the corresponding curved slots 300 in the handle fingers 200, respectively, when the handle 50 is operatively fitted to the bezel 34. It is to be noted that the height of each one of said projections 34f is preferably equal to the thickness of material used to form the fingers 200 and hence the handle 50. In addition, as clearly shown in FIG. 3, the side rims 34c and 34d have their respective side surfaces partially inwardly recessed so that the outer side surfaces of the respective handle arms 52 and 53 lie in the same plane as that of the remaining portions of the side surfaces of said side rims 34c and 34d, respectively.

Care must be taken in constructing the handle 50 such that the straight distance between the axis of each one of the pin 203 and the curved edge 101 of the corresponding one of the fingers 100 gradually increases from the point adjacent to the depth of the curved slot 300 to the point adjacent to the opening of said curved slot 300.

The handle 50 thus fitted to the bezel 34 is loosely rotatable about the pins 203 engaged in the notches 34f between a horizontal or released position in which said handle 50 lies in parallel to the substantially horizontal line and the timer module and the mounting receptacle are separable with respect to each other, and a downwardly vertical or locked position in which the handle 50 lies in parallel to the vertical line and said module and said receptacle are firmly secured with respect to each other. However, when the timer module 30 is in practice mounted onto the mounting receptacle with the cylindrical housing 31 inserted in the cylindrical body 9, the handle 50 pivots in fact about the pins 14 and 15 on the flanges l2 and 13 of the supporting plate 11, as clearly understood from the description to be made in connection with the operation of the instrument mounting assembly of the present invention. In view of this, each one of the pins 14 and 15 rotatably engageable in the corresponding one of the recesses 202 on the handle arms 52 and 53 so that the handle 50 can pivot thereabout is hereinafter referred to as a working pivot while each one of the pins 203 on the handle arms 52 and 53 loosely engaged in the respective notches 34e on the bezel 34 is hereinafter referred to as an actual pivot.

With reference to the enlarged fragmental portion of FIG. 5, in order to ensure the prevention of each one of the fingers 200 from contacting with a portion of the front surface of the flange 8 of the mounting receptacle 10 during the pivotal movement of said handle 50, the width of the notch 34e as defined by W is designed so as to be smaller than the distance between the pin 14 or 15 to the front surface of the flange 8 of the mounting receptacle 10, as indicated by D, whereby, when the timer module 30, that has been mounted to the mounting receptacle 10 is to be separated therefrom by rotating the handle 50 from the locked position to the released position, the point X of the finger 200 does not contact that portion of the front surface of the flange 8.

Details of arrangement of such elements as indicated by 14 (or 15), 34e and 34f will be hereinafter described. Each one of the pins 14 and 15 is provided on the flanges 12 and 13 in alignment with the horizontal center line as indicated by the chain line in FIG. 5, which is in turn in alignment with the corresponding one of the projections 34f on the bezel 34. Each of the notches 34f is designed so as to locate below the horizontal center line and so sized that, as the handle 50 is rotated from the released position to the locked position to secure the timer module 30 to the mounting receptacle 10, the bezel 34 or the timer module 30 can be moved straight into the mounting receptacle without displacing from the horizontal center line While the pins 203 are permitted to play within the surface areas of the notches 34e, respectively. In other words, during the straight movement of the module into the mounting receptacle effected by rotating the handle 50 as hereinbefore described, the center of roundness of the recess 202 into which the pin 14 (or 15) is rotatably engaged does not displace from the horizontal center line passing through the axis of said pin 14 (or 15) at right an-. gles to the latter. In view of the foregoing, it is clear that play of the pin 203 within the notch 34e ensures that straight movement of the timer module 30 without displacing from the horizontal center line. It is also clear that, in the case where the pin 14 (or 15) is merely pivotably inserted in a hole so that the handle is pivotable about this hole, the timer module 30 and, more particularly, the bezel 34, will be upwardly shifted displacing from the horizontal center line in which condition the terminal pins 33 will be oftentimes conditioned out of alignment with the terminal sockets in the mounting receptacle 10. Because of this, each one of the notches 34e is preferably sized such as hereinbefore described.

While in the construction as hereinbefore fully described, mounting of the timer module 30 to the mounting receptacle 10 can be executed in the following manner. This will be described with reference to FIGS. to 7.

Assuming that the cylindrical housing 31 of the timer module 30 has been already inserted in the cylindrical body 9 of the mounting receptacle 10, what is necessary to enable the handle 50 to be pivotable to the locked position is to cause the pin 14 to be situated within the recess 202. This can be easily achieved merely by keeping the handle 50in the released position while the timer module 30 is fitted to the mounting receptacle with the cylindrical housing 31 inserted in the cylindrical body 9. In this condition, the pin 203 may be located at any, position within the notch 3442.

If the handle 50 is rotated from the released position in an attempt to lock the bezel 34 to the supporting plate 11, i.e., to firmly secure the module 30 to the receptacle 10, the curved edge 101, which serves as a camming surface with respect to the projection 34f, commences to contact the projection 34f in which condition the arbitrary play of the pin 203 within the notch 34e is restricted by the lower edge of the notch 342 as clearly shown in the enlarged fragmental portion of FIG. 5 and, concurrently, the outside end extremity of each of the terminal pins 33 is slightly accommodated in the opening of the corresponding one of the terminal sockets provided in the bottom or socket member of the mounting receptacle 10.

As the handle 50 is further rotated with the application of a downwardly acting force, the pin 203 upwardly slides from the lower edge of the notch 34e to the rounded edge of the notch 342 and, thereafter, the downwardly applied force tothe handle 50 is transmitted to the projection 34f through the finger 100. The value of the force after it has been transmitted to the projection 34f must be increased as the terminal pins 33 move into the corresponding terminal sockets in the mounting receptacle 10 to ensure a rigid electrical connection therebetween.

When the increased force is applied to the handle 50 in the manner as hereinabove described to enable the handle 50 to rotate to the locked position about the working pivot, an ovencenter latching action takes place between the finger 100 and the projection 34f with the caming surface or curved edge 101 being in sliding engagement with the projection 34f and, during this process, the timer module 30 is gradually drawn close to the mounting receptacle.

FIG. 6 shows the condition in which the handle 50 attains the locked position. As clearly shown, the projection 34f is substantially situated in register with the opening of the curved slot 300 while the handle 50 is freely suspended with the pin 203 restricted by and resting on the lower edge of the notch 342. In other words, in view of the fact that, upon completion of the travel ofthe handle 50 from the released position to the locked position, the timermodule 30-is supported by j the mounting receptacle [0 with the cylindrical housing 31 and the terminal pins 33 tightly inserted respectively in the cylindrical body 9 and the terminal sockets, the force that has been applied to the handle 50 is -no longer necessary and, hence, the pin 203 that has position. However, so long as the handle 50 rotates about the working pivot 14 during this pulling operation, that is, until the pin 203 resting on the lower edge of thenotch 34a has been moved to the rounded edge of the notch 34e, no substantial force is necessary to be upwardly applied to the handle 50.

After the pin 203 has been moved to the rounded edge of the notch 34e substantially as shown in FIG. 7, a force of the value smaller than that of the force applied to bring the handle 50 to the locked position must be angularly upwardly applied to the handle 50, causing the latter to pivot about the actual pivot. In this case, because of the particular dimensional relationship between the width W of the notch 34e and the distance D between the pin 14 and the portion of the front surface of the flange 8 being such as hereinbefore described, the pin 203 acts to draw the timer module 30 out of the mounting receptacle 10 as the handle 50 is angularly upwardly moved to the released position. During this process, no contact between the camming surface 101 and the projection 34f takes place.

From the foregoing description, it has now become apparent that, during the pivotal movement of the handle 50 from the released position to the locked position, the actual pivot 203 moves from one point to another within the notch while the working pivot serves as a fulcrum about which the handle pivots and, during the pivotal movement of said handle from the locked position to the released position, the actual pivot is fixed while serving as a fulcrum about which the handle pivots. Especially, in the latter case, the working pivot or pin 14 merely acts to receive a force transmitted from the finger 200 to assist the pin 203 to draw the timer module 30 out of the mounting receptacle 10, the value of said force transmitted to the pin 14 being of a multiplication of the force which is necessary to bring the handle to the released position as envisaged from the principle of leverage.

It is to be noted that for preventing an unauthorized person from separating or removing the instrument module away from the mounting receptacle, a locking device may be provided. In the embodiment as shown, the locking device comprises an upright lug member formed on and extending integrally from a substantially intermediate portion of the grip-like portion 51 of the handle and adapted to pass a suitable screw therethrough onto a lower portion of the bezel 34, as shown. Furthermore, the cylindrical housing 31 and the cylindrical body 9 may not be always limited to the ones shown, but may be of square or rectangular cross section.

The invention being thus described, it will be obvious that the same may be varied in many ways. For example, although in the foregoing embodiment the instrument module has been described as including the cylindrical housing 31, the cylindrical housing 31 may be substituted by a plurality of frame members bridgeing between the back surface of the bezel 34 and the insulating ring 32. Alternatively, it may be omitted with the connection between the bezel 34 and the insulating ring 32 achieved by the operating mechanisms which have been described as housed in the cylindrical housing 31. In the latter case, a projection such as indicated by 343 in FIGS. 5 to 7 should beprovided as having one end rigidly secured to the back surface of the bezel 34 and the other end extending rearwardly therefrom in parallel relation to the horizontal central line for supporting the weight of the bezel 34, which is generally heavier than the rear portion of the module 30, when the module is initially inserted in the mounting receptacle.-

In view of the foregoing, such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications are intended to be included within the scope of the claims of the present invention.

What is claimed is:

1. An instrument mounting assembly which comprises a mounting receptacle having a hollow chamber, one rear end of which is closed and the other front end is open and provided with an outwardly extending .flange portion, a supporting plate secured to said flange portion and having at least a pair of frontwardly extending carrier members, each of said carrier members having at least one pin extending inwardly, a mating module having a bezel of the substantially same outline as that of said flange portion of said mounting receptacle and a cylindrical housing removably inserted in said hollow chamber of said mounting remodule, said bezel having a pair of opposed side surfaces each formed at its substantially intermediate portion with an outwardly extending projection and a notch inwardly recessed, said cylindrical housing of said mating module being adapted to therein accommodate operatively any suitable electrical and/or mechanical instrument, a substantially U-shaped handle pivoted near its open end to said notches of said bezel and adapted to be manually raised to a substantially horizontal position and lowered to a vertical position, said handle having a pair of first and second fingers on both of its parallel arms, a

curved slot formed between said first and second fingers through which said projection on both of the side surfaces of said bezel is extended and an inwardly extending recess formed at the free end extremity of said second finger removably engaging with said inwardly extending pin on both of said carrier members of said supporting plate whereby, when the mating module is to be mounted to the mounting receptacle with the cylindrical housing inserted in the hollow chamber by lowering said handle to the vertical position, said handle pivots about said inwardly extending pin on both of said carrier members of said supporting plate while said first finger on both of the open ends of said handle draws said mating module in the direction to said mounting receptacle in sliding engagement with said projection on both of the side surfaces of said bezel.

2. An instrument mounting assembly as claimed in claim 1, wherein said flange portion of the mounting receptacle and said supporting plate are integrally formed with respect to each other.

3. An instrument mounting assembly as claimed in claim 1, wherein said inwardly recessed notch loosely accommodate therein a pin provided in said handle and positioned below the depth of said curved slot for providing a fulcrum about which said handle pivots.

4. An instrument mounting assembly as claimed in claim I, wherein said projection on both of the side surfaces of said bezel and said inwardly extending pin on both of said carrier members of said supporting plate are in alignment with respect to each other and in parallel relation to the horizontal center line of said instrument mounting assembly, said inwardly recessed notch being located below a line of said alignment between said projection on both of the side surfaces of said bezel and said inwardly extending pin on both of said carrier members.

5. An instrument mounting assembly which comprises a mounting receptacle having a hollow chamber, one rear end of which is closed and the other front end is open and provided with an outwardly extending flange'portion, a supporting plate secured to said flange portion and having at least a pair of frontwardly extending carrier members, each of said carrier members having at least one pin extending inwardly, a mating module having a bezel of the substantially same outline as that of said flange portion of said mounting receptacle and a cylindrical housing inserted in said hollow chamber of said mounting receptacle, said bezel having a pair of opposed side surfaces each formed at its substantially intermediate portion with an outwardly extending projection and a notch inwardly recessed, said cylindrical housing of said mating module being adapted to therein accommodate operatively any suitable electrical and/or mechanical instrument, a handle adapted to be manually raised to a substantially horizontal position and lowered to a vertical position and having a grip portion and a pair of opposed arms integral with and extending from said grip portion, each of said handle arms being formed with a pair of first and second fingers near its open end, a curved slot formed between said first and second fingers through which said projection on both of the side surfaces of said bezel is to be extended, an inwardly extending recess formed at the free end extremity of said second fingers in removable engagement with said inwardly extending pin on both of said carrier members of said supporting plate and an inwardly extending pin formed on said second finger below the depth of said inwardly extending recess which removably loosely and pivotally engages in said notch whereby said handle is pivotally supported by said bezel and hence said mating module such that, when the mating capsule is to be mounted to the mounting receptacle with the cylindrical housing inserted in the hollow chamber by lowering said handle to the vertical position, said handle pivots about said inwardly extending pin on both of said carrier members of said supporting plate while said pin on said second finger moved one point to another within said notch causing the first finger to draw said mating module in the direction to said mounting receptacle in sliding engagement with said projection on both of the side surfaces of said bezel and, when said module, that has been mounted to said mounting receptacle, is to be separated therefrom by raising the handle from the vertical position to the horizontal position, said pin on both of said second fingers is situated to a predetermined location for serving as a fulcrum about which said handle pivots thereby permitting said second finger, with said pin on said carrier member in engagement with said inwardly extending recess, to separate said bezel and hence said module away from said mounting receptacle.

6. A rapidly replaceable timer housing assembly which comprises a mounting receptacle having a hollow chamber, one rear end of which is closed and the other end is open and provided with an outwardly extending flange portion, a supporting plate secured to said flange portion and having at least a pair of frontwardly extending carrier members, each of said carrier members having at least one pin extending inwardly, a mating module having a bezel of the substantially same outline as that of said flange portion of said mounting receptacle and a cylindrical housing removably inserted in said hollow chamber of said mounting receptacle, said be'zel including a dial plate mounted to its front and a knob-controlled pointer needleseach concentric with said dial plate and formed with a pair of opposed side surfaces each having an outwardly extending projection and an inwardly recessed notch both formed at an substantially intermediate portion thereof, a timer mechanism operatively attached to the back of said bezel and housed in said cylindrical housing,said timer mechanism including a plurality of rearwardly extending terminal pins secured to a rear end of said cylindrical housing and electrically connected with said timer mechanism, a plurality of terminal sockets in said closed rear end of said hollow chamber, each of said terminal sockets having an opening open to the interior of said hollow housing into which the corresponding one of said terminal pins is received and adapted to connect said timer mechanism therethrough to an external circuit, a substantially U-shaped handle pivoted near its open end to said notches of said bezel and adapted to be manually raised to a substantially horizontal position and lowered to a vertical position, said handle having a pair of first and second fingers on both of its parallel arms, a curved slot formed between said first and second fingers through which said projection on both of the side surfaces of said bezel is extended and an inwardly extending recess formed at the free end extremity of said second finger removably engaging with said inwardly extending pin on both of said carrier members of said supporting plate whereby, when the mating module is to be mounted to the mounting receptacle with the cylindrical housing inserted in the hollow chamber by lowering said handle to the vertical position, said handle pivots about said inwardly extending pin on both of said carrier members of said supporting plate while said first finger on both of the open ends of said handle draws said mating module in the direction to said mounting receptacle in sliding engagement with said projection on both of the side surfaces of said bezel thereby permitting said terminal pins to be firmly inserted in said corresponding terminal sockets, said inwardly extending recess on both of the second finger being, when said module is to be separated from said receptacle by raising said handle from the vertical position to the substantially horizontal position, adapted to separate said bezel away from the flange portion of said receptacle as the handle is moved to the horizontal position.

7. An instrument mounting assembly comprising: a relatively fixed mounting receptacle having a hollow chamber with an open end therein, a mating module having a housing portion with a cross-section corresponding to the cross-section of said hollow chamber, said mounting receptacle having a flanged portion adjacent the open end of said hollow chamber, said mating module having a bezel adjacent said housing portion, and handle means interposed between said flanged portion and said bezel for imparting movement of said module from a first position with said housing portion partially in said hollow chamber to a second position with said housing portion further in said hollow chamber in response to movement of said handle means in a first pivotal direction and for imparting movement of said module from said second position to said first position in response to movement of said handle means in a second pivotal direction opposite said first pivotal direction; wherein first and second pivot means interconnect said handle means to said flanged portion and said bezel such that the first pivot means serves as a relatively fixed fulcrum about which the handle means pivots and the second pivot means moves over a predeterminedpath during movement of said handle means in said first pivotal direction and such that said second pivot means serves as a fulcrum about which the handle means pivots during movement of said handle means in said second pivotal direction.

8. An assembly according to claim 7, wherein said first pivot means includes a first pivot pin fixed to said flanged portion.

9. An assembly according to claim 7, wherein said second pivot means includes a second pivot pin fixed to said handle means.

10. An assembly according to claim 8, wherein said second pivot means includes a second pivot pin fixed to said handle means.

11. An assembly according to claim 10, wherein said bezel includes a first pivot slot open in the direction facing said flanged portion, said second pivot pin engaging in said first pivot slot.

12. An assembly according to claim 8, wherein said handle means includes a slot open in the direction facing said flanged portion which engages with said first pivot pin.

13. An assembly according to claim 11, wherein said handle means includes a second slot open in the direction facing said flanged portion which engages with said first pivot pin.

14. An assembly according to claim 13, wherein said second pivot pin is disposed below said second pivot slot.

15. An assembly according to claim 14, wherein said handle means includes a third slot which is engageable with aprotrusion on said bezel for transferring forces from said handle means to said bezel during movement of said handle means in said first pivotal direction.

16. An assembly according to claim 7, wherein said handle means is constructed substantially U-shaped with the free ends of the legs of the U being interconnected by said first and second pivot means to said flanged portion and said bezel, the bridge part of the U serving as a manually engageable handle part.

17. An assembly according to claim 16, wherein said first pivot means includes a first pair of pivot pins arranged at opposite sides of said flanged portion for engagement with corresponding first slots in said free ends of said legs.

18. An assembly according to claim 17, wherein said second pivot means includes a second pair of pivot pins fixed one each to said legs for engagement with corresponding slots in said flanged portion.

19. An assembly according to claim 18, wherein respective ones of said second pair of pivot pins are positioned below respective ones of said first slots in said legs.

20. An assembly according to claim 19, wherein said handle means includes a third slot at each of said free ends of said legs which operatively engages with respective protrusions at opposite sides of said bezel for transferring forces from said handle means to said bezel during movement of said handle means in said first pivotal direction.

housing portion and said hollow chamber extend horizontally,, and wherein said third slot is configured with respect to said first and second slot such that forces transferred to said protrusion by said handle means during movement in said first pivotal direction are substantially horizontal forces only. 

1. An instrument mounting assembly which comprises a mounting receptacle having a hollow chamber, one rear end of which is closed and the other front end is open and provided with an outwardly extending flange portion, a supporting plate secured to said flange portion and having at least a pair of frontwardly extending carrier members, each of said carrier members having at least one pin extending inwardly, a mating module having a bezel of the substantially same outline as that of said flange portion of said mounting receptacle and a cylindrical housing removably inserted in said hollow chamber of said mounting remodule, said bezel having a pair of opposed side surfaces each formed at its substantially intermediate portion with an outwardly extending projection and a notch inwardly recessed, said cylindrical housing of said mating module being adapted to therein accommodate operatively any suitable electrical and/or mechanical instrument, a substantially U-shaped handle pivoted near its open end to said notches of said bezel and adapted to be manually raised to a substantially horizontal position and lowered to a vertical position, said handle having a pair of first and second fingers on both of its parallel arms, a curved slot formed between said first and second fingers through which said projection on both of the side surfaces of said bezel is extended and an inwardly extending recess formed at the free end extremity of said second finger removably engaging with said inwardly extending pin on both of said carrier members of said supporting plate whereby, when the mating module is to be mounted to the mounting receptacle with the cylindrical housing inserted in the hollow chamber by lowering said handle to the vertical position, said handle pivots about said inwardly extending pin on both of said carrier members of said supporting plate while said first finger on both of the open ends of said handle draws said mating module in the direction to said mounting receptacle in sliding engagement with said projection on both of the side surfaces of said bezel.
 2. An instrument mounting assembly as claimed in claim 1, wherein said flange portion of the mounting receptacle and said supporting plate are integrally formed with respect to each other.
 3. An instrument mounting assembly as claimed in claim 1, wherein said inwardly recessed notch loosely accommodate therein a pin provided in said handle and positioned below the depth of said curved slot for providing a fulcrum about which said handle pivots.
 4. An instrument mounting assembly as claimed in claim 1, wherein said projection on both of the side surfaces of said bezel and said inwardly extending pin on both of said carrier members of said supporting plate are in alignment with respect to each other and in parallel relation to the horizontal center line of said instrument mounting assembly, said inwardly recessed notch being located below a line of said alignment between said projection on both of the side surfaces of said bezel and said inwardly extending pin on both of said carrier members.
 5. An instrument mounting assembly which comprises a mounting receptacle having a hollow chamber, one rear end of which is closed and the other front end is open and provided with an outwardly extending flange portion, a supporting plate secured to said flange portion and having at least a pair of frontwardly extending carrier members, each of said carrier members having at least one pin extending inwardly, a mating module having a bezel of the substantially Same outline as that of said flange portion of said mounting receptacle and a cylindrical housing inserted in said hollow chamber of said mounting receptacle, said bezel having a pair of opposed side surfaces each formed at its substantially intermediate portion with an outwardly extending projection and a notch inwardly recessed, said cylindrical housing of said mating module being adapted to therein accommodate operatively any suitable electrical and/or mechanical instrument, a handle adapted to be manually raised to a substantially horizontal position and lowered to a vertical position and having a grip portion and a pair of opposed arms integral with and extending from said grip portion, each of said handle arms being formed with a pair of first and second fingers near its open end, a curved slot formed between said first and second fingers through which said projection on both of the side surfaces of said bezel is to be extended, an inwardly extending recess formed at the free end extremity of said second fingers in removable engagement with said inwardly extending pin on both of said carrier members of said supporting plate and an inwardly extending pin formed on said second finger below the depth of said inwardly extending recess which removably loosely and pivotally engages in said notch whereby said handle is pivotally supported by said bezel and hence said mating module such that, when the mating capsule is to be mounted to the mounting receptacle with the cylindrical housing inserted in the hollow chamber by lowering said handle to the vertical position, said handle pivots about said inwardly extending pin on both of said carrier members of said supporting plate while said pin on said second finger moved one point to another within said notch causing the first finger to draw said mating module in the direction to said mounting receptacle in sliding engagement with said projection on both of the side surfaces of said bezel and, when said module, that has been mounted to said mounting receptacle, is to be separated therefrom by raising the handle from the vertical position to the horizontal position, said pin on both of said second fingers is situated to a predetermined location for serving as a fulcrum about which said handle pivots thereby permitting said second finger, with said pin on said carrier member in engagement with said inwardly extending recess, to separate said bezel and hence said module away from said mounting receptacle.
 6. A rapidly replaceable timer housing assembly which comprises a mounting receptacle having a hollow chamber, one rear end of which is closed and the other end is open and provided with an outwardly extending flange portion, a supporting plate secured to said flange portion and having at least a pair of frontwardly extending carrier members, each of said carrier members having at least one pin extending inwardly, a mating module having a bezel of the substantially same outline as that of said flange portion of said mounting receptacle and a cylindrical housing removably inserted in said hollow chamber of said mounting receptacle, said bezel including a dial plate mounted to its front and a knob-controlled pointer needles each concentric with said dial plate and formed with a pair of opposed side surfaces each having an outwardly extending projection and an inwardly recessed notch both formed at an substantially intermediate portion thereof, a timer mechanism operatively attached to the back of said bezel and housed in said cylindrical housing, said timer mechanism including a plurality of rearwardly extending terminal pins secured to a rear end of said cylindrical housing and electrically connected with said timer mechanism, a plurality of terminal sockets in said closed rear end of said hollow chamber, each of said terminal sockets having an opening open to the interior of said hollow housing into which the corresponding one of said terminal pins is received and adapted to connect said timer mechanism therethrough to an external circuIt, a substantially U-shaped handle pivoted near its open end to said notches of said bezel and adapted to be manually raised to a substantially horizontal position and lowered to a vertical position, said handle having a pair of first and second fingers on both of its parallel arms, a curved slot formed between said first and second fingers through which said projection on both of the side surfaces of said bezel is extended and an inwardly extending recess formed at the free end extremity of said second finger removably engaging with said inwardly extending pin on both of said carrier members of said supporting plate whereby, when the mating module is to be mounted to the mounting receptacle with the cylindrical housing inserted in the hollow chamber by lowering said handle to the vertical position, said handle pivots about said inwardly extending pin on both of said carrier members of said supporting plate while said first finger on both of the open ends of said handle draws said mating module in the direction to said mounting receptacle in sliding engagement with said projection on both of the side surfaces of said bezel thereby permitting said terminal pins to be firmly inserted in said corresponding terminal sockets, said inwardly extending recess on both of the second finger being, when said module is to be separated from said receptacle by raising said handle from the vertical position to the substantially horizontal position, adapted to separate said bezel away from the flange portion of said receptacle as the handle is moved to the horizontal position.
 7. An instrument mounting assembly comprising: a relatively fixed mounting receptacle having a hollow chamber with an open end therein, a mating module having a housing portion with a cross-section corresponding to the cross-section of said hollow chamber, said mounting receptacle having a flanged portion adjacent the open end of said hollow chamber, said mating module having a bezel adjacent said housing portion, and handle means interposed between said flanged portion and said bezel for imparting movement of said module from a first position with said housing portion partially in said hollow chamber to a second position with said housing portion further in said hollow chamber in response to movement of said handle means in a first pivotal direction and for imparting movement of said module from said second position to said first position in response to movement of said handle means in a second pivotal direction opposite said first pivotal direction; wherein first and second pivot means interconnect said handle means to said flanged portion and said bezel such that the first pivot means serves as a relatively fixed fulcrum about which the handle means pivots and the second pivot means moves over a predetermined path during movement of said handle means in said first pivotal direction and such that said second pivot means serves as a fulcrum about which the handle means pivots during movement of said handle means in said second pivotal direction.
 8. An assembly according to claim 7, wherein said first pivot means includes a first pivot pin fixed to said flanged portion.
 9. An assembly according to claim 7, wherein said second pivot means includes a second pivot pin fixed to said handle means.
 10. An assembly according to claim 8, wherein said second pivot means includes a second pivot pin fixed to said handle means.
 11. An assembly according to claim 10, wherein said bezel includes a first pivot slot open in the direction facing said flanged portion, said second pivot pin engaging in said first pivot slot.
 12. An assembly according to claim 8, wherein said handle means includes a slot open in the direction facing said flanged portion which engages with said first pivot pin.
 13. An assembly according to claim 11, wherein said handle means includes a second slot open in the direction facing said flanged portion which engages with said first pivot pin.
 14. An assembly according to claim 13, wherEin said second pivot pin is disposed below said second pivot slot.
 15. An assembly according to claim 14, wherein said handle means includes a third slot which is engageable with a protrusion on said bezel for transferring forces from said handle means to said bezel during movement of said handle means in said first pivotal direction.
 16. An assembly according to claim 7, wherein said handle means is constructed substantially U-shaped with the free ends of the legs of the U being interconnected by said first and second pivot means to said flanged portion and said bezel, the bridge part of the U serving as a manually engageable handle part.
 17. An assembly according to claim 16, wherein said first pivot means includes a first pair of pivot pins arranged at opposite sides of said flanged portion for engagement with corresponding first slots in said free ends of said legs.
 18. An assembly according to claim 17, wherein said second pivot means includes a second pair of pivot pins fixed one each to said legs for engagement with corresponding slots in said flanged portion.
 19. An assembly according to claim 18, wherein respective ones of said second pair of pivot pins are positioned below respective ones of said first slots in said legs.
 20. An assembly according to claim 19, wherein said handle means includes a third slot at each of said free ends of said legs which operatively engages with respective protrusions at opposite sides of said bezel for transferring forces from said handle means to said bezel during movement of said handle means in said first pivotal direction.
 21. An assembly according to claim 20, wherein said third slot is configured such that all forces transferred to said bezel by said handle during movement of said handle means in said second pivotal direction are through means other than said third slot and said protrusions.
 22. An assembly according to claim 20, wherein said housing portion and said hollow chamber extend horizontally,, and wherein said third slot is configured with respect to said first and second slot such that forces transferred to said protrusion by said handle means during movement in said first pivotal direction are substantially horizontal forces only. 